1. Field of the Invention
The present invention relates to an animal health care system for effecting health care for various kinds and sizes of animals by measuring weight and impedance of the animals and calculating health assessment data such as body fat rate, body water mass and the like for assessing health condition of the animals.
2. Prior Art
In the conventional health care for animals, in order to judge the degree of adiposity of a dog and a cat, for example, it was common for a veterinary to perform an ocular inspection or a palpation for judging the degree of adiposity using Body Condition Score (hereafter referred to as “BCS”) which classifies the animal into five ranks from slender to fat (see non-patent document 1, for example).
A number of researches have previously been conducted in which bioelectrical impedance of an animal is measured and the data such as body fat rate, body water mass and the like is calculated, as in the case of human being. Various kinds of animals such as a dog, a cat, a sheep, a pig, a rat, etc., have been used in those researches as the specimen. Several types of method for impedance measurement and for electrode placement have been developed, but most of them are of invasive type, that is to say, a needle-like electrode is pierced into the skin of the animal for impedance measurement. Then, any correlation between the resultant impedance value and the body composition analysis due to “DEXA” measurement or the dead body analysis is examined. Among others, the following two researches have been disclosed wherein the specimen is a dog and the impedance measurement is conducted in non-invasively without any injury to the animal.
In a first research, a dog is suspended by a fixing device in such manner that the dog is restricted in posture while standing on all four legs, but spaced away from the floor. A measurement person wears a set of gloves on both hands each having a current supplying electrode for impedance measurement affixed on the palm portion thereof, and grasps both front legs of the dog at the predetermined positions for making contact the electrodes on the gloves therewith. Then, another person wearing a set of gloves having voltage measurement electrodes affixed thereto grasps both rear legs of the dog in the same manner for conducting measurement of impedance between the front and rear legs of the dog.
According to the well known theorem for impedance measurement in which body water mass is proportional to square of distance between impedance measurement points, but inversely proportional to the impedance value, the body length of the dog is separately measured, which is used instead of the distance between impedance measurement points, the body water mass is estimated based on the body length and the impedance value, and the body fat rate is calculated based on the body water mass thus estimated and the weight value separately measured. (see non-patent document 2, for example)
In a second research, it is assumed that when the impedance measurement is done by positioning the electrodes at the root of legs that are near to the main body with body hair shaved then more stable impedance value is resulted than when the electrodes are positioned on the legs that are far away from the main body. Therefore, while the dog is sleeping with the face upward under anesthesia the impedance measurement is done diagonally across the body between the front right and rear left legs or between the front left and rear right legs. Again, according to the well known theorem for impedance measurement in which body water mass is proportional to square of distance between impedance measurement points, but inversely proportional to the impedance value, the body length of the dog is separately measured, which is used instead of the distance between impedance measurement points, and the body water mass is estimated based on the body length and the impedance value. (see non-patent document 3, for example)
Further research has been disclosed in which the weight value is estimated according to regression formula which is derived based on correlation between the weight value and each morphologic measurement value such as body length, body height or girth of trunk of an animal. Among those, the highest correlation is resulted between the weight value and the girth of trunk, which is illustrated as correlation factor “r”=0.85. (see non-patent document 4)
Furthermore, it is well known that the metabolism of an animal in rest condition or the basal metabolism of an animal depends on its body temperature. In case of a human, calculation of metabolism based on fat free mass is conducted using the body temperature as the correction term (see non-patent document 5, for example).
The reference documents are as follows:
Non-patent document 1: “Healthy Diet for Dog”, Masayuki Aoyagi, K. K. Enter Brain, Oct. 27, 2001, pages 14 to 15;
Non-patent document 2: “Examination of Bio-Impedance Method for Dog's Body Fat Rate Measurement Method”, Tomoko Oshima, Fumio Nakato, and two others, VETERINARY CLINICAL PATHOLOGY ACADEMY,
Non-patent document 3: “Impedance electrodes positioned on proximal portions of limbs quantify fluid compartments in dogs”, MARC R. SCHELTINGA, and four others, USA, the American Physiological Society, 1991;
Non-patent document 4: “A rapid method for determining normal weights of medium-to-large mongrel dogs”, PAULA B. PENDERGRASS, and four others, BSAVA, 1983; and
Non-patent document 5: “Nutritional Physiology and Biochemistry”, Harutoshi Yoshikawa, K. K. Koseikan, Feb. 25, 1987, Page 16.
However, judgment for degree of adiposity for an animal using “BCS” is governed by subjectivity of a veterinary who conducts an ocular inspection or a palpation, which highly depends on experience and perception of the veterinary, and therefore, there is tendency that the result of judgment varies widely or there is possibility that misjudgment is made. In addition, in case where an owner of an animal having no professional skill readily conducts judgment of adiposity of the animal at home there may possible that the result of judgment varies more and more widely. As the result, it may happen that the animal is given too much food, thereby making the animal more adipose, or inversely the animal becomes too slender, thereby loading greater burden to the animal.
Although many researches for measurement of impedance of an animal have been made, as described above, most of them are of invasive type so that they are impractical in the relevant field. In addition, two specific researches are described above wherein the specimen is a dog and the impedance measurement is conducted in non-invasively to derive body fat rate, body water mass, etc., as in the case of human being. However, as described above, in the first research, the fixing device is necessary for fixing the dog while it is suspended. In such case, when measurement of bigger dog is necessary, the size of the fixing device should be increased accordingly. Furthermore, in order to make contact the electrodes to both front legs and both rear legs of the dog, two persons are necessary to grasp the legs of the dog, which is very tedious task. In this regard, there is possibility of an error occurred in measurement due to misalignment of the electrode to the predetermined position of the leg depending on the manner the person grasps the leg. Moreover, it is necessary to separately measure the weight and body length of the dog for calculating the health assessment data such as body fat rate, body water mass, etc., which takes longer period of time and needs much labor. The body length separately measured is simply used instead of the distance between the measurement electrodes, which may be an error source for calculation of the health assessment data, for example.
In the second research, because of substantially no such animals that are immobile with the face upwardly during the measurement of impedance, it is necessary that the animal sleeps under anesthesia, which is impractical irrespective of the fact that the impedance measurement can be conducted in non-invasively. Again, the body length of the animal is separately measured and used instead of the distance between the measurement electrodes, which may be an error source for calculation of the health assessment data.
In this manner it can be said that technique for measurement of bio-impedance of an animal still remains in the course of studying and research phase and no systems for readily conducting animal health care and suitable for practical use have been provided.
In addition, the system for estimating weight value using the regression formula derived from the correlation between the weight value and the girth of trunk of an animal has not been studied to such level that the health care of the animal is effected using the estimated weight value.
Furthermore, such living body measurement system has been well known that acts as a human adiposity judgment system for indicating tendency of adiposity for human by measuring body fat rate using “BIA” technique. However, no animal body fat rate calculation system in which various kinds of and different sizes of animals can be accepted for measurement has been put into practice.
Moreover, in case of an animal, especially, a dog, the body temperature depends on its body build and varies widely over various kinds of dogs. The metabolism of dog can be calculated using the fat free mass and the body temperature, as in the case of a human whose metabolism is previously calculated using the body temperature as the correction term. But, measurement of body temperature of dog takes longer period of time because of temperature of rectum mainly measured, which makes the temperature measurement very difficult.
Because of no device developed for calculating consumption and intake energy for each of dogs it has been common that food is given without knowing the proper amount for the dog. Accordingly, there may happen that food is given too much or too less, with the result that insufficient health care including adipose condition can frequently be resulted.
In view of the above, an object of the present invention is to provide an animal health care system that conveniently allows health care of an animal even at home.
Another object of the present invention is to provide a dog health care system for effecting health care for dog by deriving the metabolism of dog that is corrected using body temperature correction factor according to kinds or body builds of dogs.